Debt - Interest expense (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2023	Apr. 02, 2022
Interest expense related to the notes
Interest Expense, Total	$ 1,656	$ 1,680
Convertible Senior Notes
Interest expense related to the notes
Contractual interest expense	845	845
Amortization of debt issuance costs	523	496
Interest Expense, Total	$ 1,368	$ 1,341

Amount of the cost of borrowed funds accounted for as interest expense.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Name:	us-gaap_InterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration